Safety mechanism for nailing machines



`April 21,1942. J. A. DURAN 2,280,189

SAFTY MECHANISM FOR NAILING MACHINES Filed Feb. 7, 1941 Patented Apr;21,1942v SAFETY MECHANISM `Fort l MACHINES l NAILIN G John. Duran,BeverlyMass.`, assignor to United ShoeMachinery Corporation, Flemington,N.`J.,

a corporation of New Jersey .Application February 7,1941, serial No.377,877

6 Claims. I

This invention relates to means for protecting `the operators of suchnailing machines as those employed for attaching heels to shoes, frominjury caused by the accidental starting of the machine in operation.`

In an apparatus of the character of that `disclosed in Letters Patent ofthe United States No.

1,157,688, Glidden, October 26, 1915, a hinged guard is placed in irontof the `reciprocatory nailing die and its co-operating drivers. Whenraised, this guard covers the"movable parts behind it, so'the operatorshands cannot come in Contact with them.` VWhen lowered, access may behad to the die and drivers to allow them-to l beinspected orchanged.Careless operators may leavethe guarddown, or even entirely removeitbecause they feel it slows them in their work With the movableelements thus exposed,the starting treadle of the machine. may bedepressed accidentally,"` causing said machine to go through anoperating cycle.` The operator-s `hands might then be caught by thenormally guarded moving parts, or hishead struck by the descending jack,forcedfdown for the application of preliminary pressure to the work. Anobject of this invention is to give the operator effective protectionagainst' such accidents;

In the attainment of the above object, there is combined withnail-driving mechanism, as a die and co-operating' drivers, theirshielding guard,

means by `whichthe driving mechanism is operated and a treadle or othercontrolling member for such means, locking members of which there may betwo, one connected to the controlling member and the ,othermovable intoand out of the path of the first and connected to the guard. Thisarrangement may be caused to prevent actuation of the treadle and thestarting of the machine, when the movable parts are exposed, but willpermit operation if these are covered. To render it diiiicult for theoperator to take off the guard, and thus be completely deprived of itsprotection, I have furnished means for pre-f the associated elements topreventv ready separation.

The drawing illustrates a single embodiment of the invention, it showingmy improved safety mechanism in broken side elevation.

Of the machine of the previously mentioned patent, there appears a frameI0, upon which are guided for vertical reciprocation a crosshead I2,carrying a die-block I4, and a crosshead 1I6, upon which` is mounted aplate having drivers I8 movable in nail-receiving passages in thedie-block. From a power-shaft 20, the crossheads `I4 and IG arerespectively `actuatedby connections in cluding toggle levers 22 and 24.In the connections to the crosshead I6, a cam-lever 26 is`ineluded, themovement of which is governed by a cycle.

cam-slot 28 formed in it and guided by a projection 3B from the frame,Power` is applied to the shaft 2E) through a single-`rotation clutchmecha` nism 32, which is tripped by depression of `a treadle 34,fulcrumed upon a spindle 36. Connected to the treadle by a link 38 is alocking bar 40, joined at its opposite extremity to the center of thetoggle-lever 22.` When the treadle is depressed in the normal operationof the machine, the link 38 lifts a shoulder 42 upon the bar clear of apin 44 projecting laterally from an arm 46 attached to the spindle 33,this allowing full depression ofthe treadle to initiate an operating Asa protection `to the operator from the l power-actuated parts of thenailing mechanism,

there is hinged in front of these parts `upon a pin 48, lying in ahorizontal bore in the frame,

venting disconnectionof the pivoted connections between the lockingmember andlguard,`w`hen l the elements are assembled. In the particularform ofthe invention herein disclosed, the

a guard 50. When this guard is raised to the position shown in fulllines in the drawing, the

movab-le elements are completely shielded from contact with theoperator, but it may be swung outwardly and downwardly to give fullaccess to these elements. This relation `is indicated in dotted lines.

Considering now what is peculiar to the present invention, a boss 52projects from the guard 50 and xed in the boss at one side of the axisand parallel thereto, is a pivot-pin 54. This pivot-pin is joined by alink 56 to a pivot-pin 58 lying in a recess at oneside of a stoparm`60mounted to swing about the frame-projection 30. When the guard 50 is inits raised relation, a transversely extended surface 62 upon the lowerend yof the arm 60 lies clear of an upward projection 64 from thestop-bar. It will be seen that under these conditions, upon elevation ofthe locking bar 4l] with its projection 64 by depression ofthe treadle34, said bar will be free for movement, so the clutch 32 may be trippedto TENT OFFICE start the machine in operation. When, however, the guardis lowered, the pin 54, which is in effect a crank-pin, rotatesclockwise, drawing the link 56 to the right. This similarly swings thearm 60 until its surface 62 is just above the top of the projection 64.If there is occasion to remove the guard, excessive movement of the armin this direction is limited by a shoulder 66 upon the arm. The relationof the elements for the lowered position of the guard is as illustratedin dotted lines in the drawing. Now, if an attempt is made to treadlethe machine, the bar 40 cannot rise, so it is impossible to release theclutch for driving engagement. Thus, the operator is positivelyprotected from injury by moving parts of the machine, whether these bein the rising die mechanism and driver mechanism, or the unillustrateddescending jack mechanism. To make it hard for the operator to uncouplethe safety connections while the associated elements are in place, thepivot-pin 54 is driven into the boss 52 and the adjacent end of the link56 lies in a circumferential groove formed between a head l upon thehinge-pin 48 of the guard 58 and the outer surface of the boss, thehinge-pin being secured tothe boss at 12. The opposite extremity of thelink and the pivot-pin 58 are similarly situated between the cam-lever28 and the arm 60. The retaining nut 'i4 of the cam-lever 26 may also bepinned at 76 to the frame-projection 30. The diculty involved indisconnection will usually prevent the operator from tampering with thesafety mechanism.

Having described my invention, what I claim as new and desire to secureby Letters Patent of the United States is:

l. In a nailing machine, nail-driving mechanism, a guard movable toshield or give access to said mechanism, operating means for the drivingmechanism, a movable controlling member for the operating means, alocking member connected to the controlling member, and a second lockingmember movable into and out of the path of the rst locking member andconnected to the guard.

2. In a nailing machine, a nailing die, naildrivers co-operatingtherewith, the work-engaging portions of said die and drivers being atall times free for the association with and removal of work therefrom, aguard movable to either shield or give access to the die and driversbelow their work-engaging portions, operating means for the drivers, amovable controlling member for the operating means, and means movableunder the influence of the guard to lock the controlling member againstmovement or to release it for actuation.

3. In a nailing machine, nail-driving mechanism, a guard pivotallymounted to be swung between the operator and the nailing mechanism orlowered to give access to said mechanism, operating means for thenailing mechanism, a movable controlling member for the operating means,and locking means for the controlling member, said means including alocking member and a connecting member pivoted to the locking f' memberand to the guard, there being means for preventing the manualdisconnection of the connecting member at its pivots while theassociated elements are assembled,

4. In a heel-attaching machine, a frame, a nailing die and reciprocatorydrivers mounted upon the frame, a guard pivoted upon the frame and lyingnormally in front of the die and drivers below the point of applicationof work thereto, operating means for the drivers, treadle mechanisrn bywhich the operating means is controlled, and a locking member for thetreadle mechanism pivoted upon the frame and connected to the guard.

5. In a heel-attaching machine, a frame, nailing mechanism including adie and reciprocatory drivers movable upon the frame, a guard pivotedupon the frame in front of the die and drivers, operating means for thedrivers, a treadle by which the operating means is controlled, a lockingbar movable by the treadle and nailing mechanism, an arm pivoted uponthe frame and movable into and out of bar-retaining relation, and a linkjoining the arm to the guard.

6. In a heel-attaching machine, a frame, a nailing die and reciprocatorydrivers mounted upon the frame, a guard pivoted upon the frame in frontof the die and drivers, operating means for the drivers, a treadle bywhich the operating means is controlled, a locking bar co-operating withthe treadle, an arm pivoted upon the frame and movable into and out ofbar-retaining relation, and a link pivotally connected to the arm andguard, the ends of the link at the pivots being covered and renderedinaccessible by the associated elements to prevent separation.

JOHN A. DURAN.

